Can life survive in an underground Antarctic lake?

December 21, 2012

Can it?

An international team of scientists say an expedition searching for life within Antarctica’s Lake Vostok has yet to produce evidence of a single native organism, although they say they will continue to conduct research until the findings are conclusive.

Preliminary research seems to suggest that the lake is lifeless. In a report published on Friday, researcher say the first samples retrieved from the underground lake do not contain any evidence of life. Scientists reportedly expected to discover signs of bacteria in two places within the subglacial lake: at the top of the lake between the ice and the water, and in the sediment at the bottom of the lake.

“A first analysis of the ice that froze onto the drillbit used in last February’s landmark drilling to a pristine Antarctic lake shows no native microbes came up with the lake water,” according to Sergey Bulat of Petersburg Nuclear Physics Institute (Russia). The very uppermost layer of Lake Vostok appears to be “lifeless” so far, says Bulat.

Researchers analyzed the microbes present in the ice sample, checking their genetic makeup to figure out the phylotypes. They counted fewer than 10 microbes/ml — about the same magnitude they would expect to find in the background in their clean room. Three of the four phylotypes identified matched contaminants from the drilling oil, with the fourth unknown but also most likely from the lubricant.

Lake Vostok is a liquid freshwater lake the size of Lake Ontario, buried beneath more than 2 miles of ice and rock for at least the past 14 million years. It remains one of the most isolated environments on Earth, which could provide researchers with an idea of what type of organisms thrived millions of years ago. In Antarctica, some 387 lakes have so far been found underneath the thick ice sheet, prompting interest from the scientific community.

The report comes months after a team of Russian scientists announced that, after more than ten years, they had successfully drilled through 2.5 miles of ice to reach the lake. Scientists believed the lake may hold “extremophiles,” organisms that can survive nearly impossible conditions. The discovery of such lifeforms would likely boost support for discovering life on different planets, including Mars, where harsh conditions would likely mean only the most adaptable organisms would survive.

The Russian researchers say they plan to continue to carry out tests in the future, adding that the first samples are simply the first step towards examining a large portion of the lake.

“It’s based on ice found on their drill, so it’s a very contaminated sample. Secondly, when you take liquid water and freeze it, there’s a partitioning—99 percent of the impurities, including microorganisms, are not being incorporated into the ice,” says Bulat. “The verdict is still out. We really need to go into the lake and sample it properly with sterile instruments.”

The initial report was published this week at the 12th European Workshop on Astrobiology in Stockholm, Sweden.

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